1. Field of the Invention
The present invention relates to a control apparatus for a vehicle which can cooperatively control various control systems mounted on an automobile.
2. Description of the Related Art
Mounted on an automobile are an engine control system, a transmission control system, and other various control systems for controlling the motion or attitude of the automobile. Such control systems include a skid control system, electric power steering system, active damper system, active stabilizer system, adaptive cruise control system, and 4WD control system.
Further mounted on the vehicle is a sensor unit incorporating various acceleration sensors for detecting accelerations required for the control of the above control systems and various angular velocity sensors for detecting yaw, roll, and pitch rates of the vehicle. The conditions of the various control systems are individually detected depending on the respective purposes, and the control systems are individually controlled by using the accelerations and/or angular velocities detected in the sensor unit.
Japanese Patent Laid-open No. Sho 62-260283 discloses a sensor signal processing apparatus for an automobile such that a plurality of signals from various sensors mounted on the automobile are input into the processing apparatus and processed so as to allow easy use by various control units, and these processed signals are distributed to the various control units. Further, Japanese Patent Laid-open No. Sho 62-260284 discloses a sensor signal processing apparatus for an automobile such that a plurality of signals from various sensors mounted on the automobile are input into the processing apparatus and processed so as to allow easy use by various control units, that these processed signals are distributed to the various control units, and that information processed in the various control units is interchanged therebetween. Further, Japanese Patent Laid-open No. Hei 5-262190 discloses an integrated control apparatus for an automobile such that the number of wires required for integrated control of the automobile is reduced.
With the advance of an electronic control system for an automobile, it has been found that the cooperative control of various control systems rather than the individual control thereof has great value. Accordingly, a control unit for performing integrated cooperative control of the various control systems is necessary. If the control unit is mounted as new hardware, a cost increase and an increase in installation area for an electronic control unit are invited.
In the technique disclosed in Japanese Patent Laid-open No. Sho 62-260283, the sensor signal processing apparatus merely functions to process the signals from the various sensors so that the control units can easily use the input signals and to distribute the processed signals to the control units. Further, in the technique disclosed in Japanese Patent Laid-open No. Sho 62-260284, the sensor signal processing apparatus includes the configuration of the technique disclosed in Japanese Patent Laid-open No. Sho 62-260283 and has an additional function of controlling the control units so that the information processed in the control units can be interchanged therebetween. However, there is no mention in each publication cited above as to whether the sensor signal processing apparatus is connected to each control unit so as to allow bidirectional communication and performs integrated cooperative control of the control units.